The present invention relates to the placement of aneurysm grafts and the instruments necessary to accomplish such placement. In particular, the present invention provides a guide steering device having exposable wire loops and a steering system for placement of an aneurysm graft limb.
As shown in FIG. 1, an abdominal aneurysm graft 80 is used to allow blood to bypass the site of an abdominal aortic aneurysm 61 and pass to iliac vascular branches 62 there from without obstruction or backflow. The abdominal aneurysm graft 80 has a main body 64 and is bifurcated into ipsilateral 66 and contra-lateral 67 limbs at its proximal end. The limbs (66, 67) are meant for placement within iliac vascular branches 62 which branch off from the abdominal aorta 69.
In the last several years, the field of minimally invasive surgery has grown exponentially. As a result, even stent and graft placement has been affected. Presently, placement of an abdominal aneurysm graft 80 is accomplished by way of a minimally invasive catheterization technique. A guidewire 68 is inserted through a patient""s vasculature and eventually through an iliac vascular branch 62 to the site of the aortic aneurysm 61. A balloon catheter (not shown) equipped with a capsule containing the aneurysm graft to be placed is delivered to the site of the aneurysm via the guidewire 68. The balloon portion of the catheter and the capsule are separable in order to deploy the main body 64.
Once the main body 64 is deployed, the balloon portion of the catheter may be positioned within the deployed main body 64. The balloon may then be inflated in order to anchor the main body 64 against the walls of the abdominal aorta 69 above the iliac bifurcation 71. Surgical hooks (not shown) may be provided at an outer portion of the main body 64 to promote its anchoring against the walls of the abdominal aorta 69 during this inflation.
As the main body 64 is deployed, an ipsilateral limb 66 may be exposed as attached to the main body 64. If this is the case, only a contra-lateral limb 67 will need to be added to the main body 64 in order to complete bypass of the aortic aneurysm 61 through the opposite (i.e. contra-lateral) iliac vascular branch 62. On the other hand, if the ipsilateral limb 66 is not initially provided as attached to the main body 64, it may be desirable to add it once the main body 64 is secured within the aortic aneurysm 61. Again, placement of the ipsilateral limb 66 is necessary to complete bypass of the aortic aneurysm 61 via the iliac vascular branch 62 through which the catheter has initially been introduced to the site.
If complete bypass via iliac vascular branches 62 is desired at this point, there is still a need to attach at least one graft limb subsequent to deployment of the main body 64. As indicated above, placement of the ipsilateral limb 66 is accomplished by either providing the ipsilateral limb 66 simultaneous with the main body 64 or by subsequently advancing the ipsilateral limb 66 to the site of the main body 64 via the guidewire 68 which has already been delivered. However, neither of these options is available for placement of the contra-lateral limb 67. Rather, it is necessary to have a separate guide for a separate advancement of the contra-lateral limb 67 to the site of the main body 64. Unfortunately, it is very difficult to reach an implanted main body 64 in order to guide and subsequently attach the contra-lateral limb 67. This is because the aortic aneurysm 61 has a width which is much greater than either of the iliac vascular branches 62. Thus, once a limb delivering mechanism, such as a catheter adapted therefore, is advanced through an iliac vascular branch 62 to the site of the aortic aneurysm 61, it must traverse the aortic aneurysm 61 in an unguided manner and enter the main body 64 in order to subsequently deliver the contra-lateral limb 67.
The difficulty associated with placement of a contra-lateral limb 67 has been addressed by simply blocking off one of the iliac vascular branches 62 and utilizing a graft which is equipped with only the ipsilateral limb 66. However, this requires a subsequent more invasive surgical procedure to place a femoro-femoral bypass between the iliac vascular branches 62 in order to redeliver a flow of blood to the blocked iliac branch, proximal (i.e. below) the aortic aneurysm 61. Thus, many of the advantages of minimally invasive surgery have been lost. Alternatively, a second guidewire may be inserted through a patient""s vasculature distal of the aortic aneurysm 61 and through the main body 64. Thus, once the entire abdominal aneurysm graft 80 is deployed, a guidewire will be present through both iliac branches. One or both of these guidewires may be used to aid in subsequent placement of limbs (66, 67). However this is a more complex procedure which requires additional incisions above (or distal) the aortic aneurysm 61 for external maintenance of the additional guidewire and introduction of the abdominal aneurysm graft 80. Lastly, an abdominal aneurysm graft 80 may be used without limbs (66, 67) at all. However, such an abdominal aneurysm graft 80 is not highly stable and does not provide an efficient bypass.
Therefore, what is desired is a system for placement of a contra-lateral aneurysm graft limb in a minimally invasive manner via a minimal number of incisions. It may be desirable to develop a system capable of delivering a second guidewire to the site of an aneurysm to aid in subsequent placement of a graft limb without requiring additional incisions above (or distal) the aneurysm.
The present invention provides a guidewire placement system for delivery of an aneurysm graft limb. The system may include steerable external tubing with an advanced flexible region which may be directed by manipulation of a steering wire.
The guidewire placement system may include guide tubing. The guide tubing is equipped with wire loops at a distal end thereof to promote accessibility of an aneurysm graft during guidewire placement.
The present invention also provides a method of providing a contra-lateral limb to a graft. The method may involve advancement of external tubing to the site of an aneurysm and graft while manipulating a steering wire which promotes movement of a distal extension of the external tubing toward a proximal contra-lateral portion of the graft.
The method may involve use of guide tubing. The guide tubing is advanced to the site of an aneurysm and graft where the tubing is further advanced into the graft followed by delivery of a guidewire.
The present invention provides a system for graft delivery to an aneurysm. The system may include a graft and a limb deployment catheter as well as means for advancing a contra-lateral guidewire into a placed graft.